Isolation and Characterization of A High-efficiency Atrazine-degrading Strain Paenarthrobacter ureafaciens ZF1

The widely use of atrazine causes great threat to the environment. Microbial degradation is an effective method to quickly remove atrazine to maintain environmental safety. A bacterial strain, ZF1, capable of highly degrading atrazine which could grow with atrazine as both carbon and nitrogen sources, was isolated from the wheat field soil in Henan Province, China. Phenotypic characterization and 16S rRNA gene sequencing indicated that the isolate belonged to the Paenarthrobacter ureafaciens. Polymerase chain reaction（PCR） analysis revealed that ZF1 contained the atrazine-degrading genes trzN, atzB and atzC. The growth and atrazinedegradation efficiency of strain ZF1 had broad ranges of temperature（5℃-50℃） and pH（5.0-11.0）, and had a high tolerance to atrazine and could tolerate at least 1 500 mg · L^-1. The addition of carbon and nitrogen sources promoted the degradation rate of atrazine to a certain extent. When the strain was cultured with starch as carbon sources, the degradation rate of atrazine could reach 50 mg · L^-1 · h^-1.In general, the discovery of strain ZF1 enriched the resources of atrazine degrading strains. Its excellent biodegradability and environmental tolerance showed that strain ZF1 had great potential in the bioremediation of atrazine contaminated sites in the future.